1. Field of the Invention
The present invention is in the field of gas leak detection and measurement and is specifically concerned with the detection and measurement of radioactive tritium gas leaks.
2. Description of the Prior Art
It is essential that sealed containers of tritium gas be determined to be free of any leaks before the containers are handled by plant personnel or moved into production areas.
Flow-through type detector systems are currently used to detect escaping tritium gas. In this type of detector system a container containing tritium is disposed in a chamber, an inert gas, as for example, argon is caused to flow through the chamber around the container of tritium gas through the associated plumbing and through an ionization chamber. In the ionization chamber, the gas sample passes between two electrodes disposed within the chamber. The electrodes are connected to an ammeter outside of the chamber. If the gas sample completes a dc electrical circuit between the electrodes, the current flow is measured on the ammeter. Any reading at all on the ammeter is an indication of the presence of tritium gas. The amount of current measured by the ammeter can be equated to the amount of tritium gas in the sample.
This prior art detection process dilutes the tritium gas be dispersing it throughout the test chamber, the ionization chamber and the associated plumbing. This dilution of the sample reduces the sensitivity of the system and increases the processing time necessary to obtain statistically significant results.
The process often requires from 30 to 40 minutes of running time. Such a lengthy period of running can and frequently does, result in electromagnetic interference which manifests itself as noise in the counting system, thus making the readings unreliable.